This collection of essays advocates a different vision of international law for environmental protection and sustainable development. The perspective is widened beyond the traditional focus of so-called public international law. This is mainly concerned with territorial sovereignty, state responsibility, inter-state treaties and intergovernmental organizations. It encompasses neighbouring branches of law that are equally and increasingly relevant to transnational environmental relations and governance, including: private international law, in particular techniques and channels for the settlement or avoidance of conflicts primarily involving participants other than states; and international administrative law, in particular competing claims by authorities to regulate the environmental aspects of economic activities.